COMMUNICATION CONTROL SYSTEM, COMMUNICATION CONTROL METHOD, AND CALL ORIGINATION CONTROL SIP SERVER

摘要

PROBLEM TO BE SOLVED: To provide a communication control system, a communication control method, and a call origination control SIP server that enable communication between IP telephone subscriber terminals without being influenced by congestion regulation of a SIP server implemented in an IP telephone network.SOLUTION: A call origination control SIP server connected to IP telephone subscriber terminals and a subscriber server (SIP server) transmits a connection request signal to a plurality of prescribed IP telephone subscriber terminals to enable telephone conversation between the prescribed IP telephone subscriber terminals on the basis of subscriber information the subscriber server comprises in the case where the subscriber server which accommodates the IP telephone subscriber terminals and performs call connection control at the normal time has been congestion-controlled.